Manufacture of bags



Aug. 11, 1964 A. F. BECKER MANUFACTURE OF BAGS 3 Sheets-Sheet 1 Original Filed Sept. 26, 1961 Aug. 11, 1964 A. F. BECKER MANUFACTURE OF BAGS 5 Sheets-Sheet 2 Original Filed Sept. 26, 1961 Aug. 11, 1964 A. F. BECKER MANUFACTURE OF BAGS 3 Sheets-Sheet 3 Original Filed Sept. 26, 1961 .for example, in Rawe US. Patent 2,707,421. shows one end of each tube of such a series of tubes being United States Patent 3,143,936 MANUFACTURE OF BAGS Arnold F. Becker, San Pedro, Calif, assiguor to Benns Bro. Bag Company, St. Louis, Mo., a corporation of Missouri Original application Sept. 26, 1961, Ser. No. 140,810. Divided and this application Sept. 10, 1962, Ser. No.

4 Claims. or. 93-35 This invention relates to the manufacture of bags, and more particularly to a method of manufacturing valve sleeves for pasted valve bags.

This application is a division of my copending application Serial No. 140,810, filed September 26, 1961, entitled Bags, issued as US. Patent 3,129,871, April 21, 1964. In said parent application there is disclosed and claimed an improved tuck-in valve sleeve for pasted valve bags, which sleeve has a cuff providing ample space for tuck-in of the sleeve after the bag has been filled. This divisional application relates to a method of manufacturing such cuffed sleeves for application to bags being fed through a bottomer, its object being the economical manufacture of these sleeves in quantity production, from a continuous Web of sleeve material and in such manner that the sleeves as completed may be combined with bags in a continuous operation. Other objects and features will be in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the methods hereinafter described, the scope of the invention being indicated in the following claims.

In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

FIG. 1 is a schematic side elevation showing the manufacture of bags in accordance with this invention;

FIG. 2 is a perspective illustrating certain steps performed in FIG. 1;

FIG. 3 is a top plan view of a string of sleeves made according to FIGS. 1 and 2 and showing a sleeve segmented from the string;

FIG. 4 is a bottom plan of FIG. 3; I FIGS. 5 and 6 are enlarged detail views;

FIG. 7 is a schematic plan view showing bag tubes being fed through a sidewise bottomer and having sleeves 'applied thereto; and

at 1 in FIGS. 1 and 7 a bag bottomer of a type such as is referred to in the art as a sidewise bottomer. understood that in this type of bottomer, flat bag tubes B It will be are fed forward sidewise (as distinguished from lengthwise) one after another, and the ends of each tube are formed with pasted closures. Such a bottomer is shown, FIG. 7

fed forward one after another through the sidewise bottomer, this end being the end including the corner of the tube where a valve is to be formed and a valve sleeve ,8 applied. As shown for the tube at the left of FIG. 7,

stripe extending across valve flap 3 has a relatively narrow portion P1 extending closely adjacent the inner end edge of flap 3 between lines L1 and L2 on which 3,143,936 Patented Aug. 11, 1964 ice flaps 7 and 9 are subsequently folded to complete the closure. The flaps 3 and 5 are oriented lengthwise as regards the direction of feed of the bag tubes. The bag tubes are fed forward from left to right as viewed in FIGS. 1 and 7 (as indicated by the arrows in FIG. 7), at a predetermined speed, with the bag tubes equally spaced. As the bag tubes are fed through the bottomer, and after the end of each bag tube is opened up and paste P applied, a valve sleeve S is applied to valve flap 3. In FIG. 7, a sleeve S has been applied to the bag tube at the center. Then, as shown for the tube at the right of FIG. 7, side flap 7 is folded over on line L1 on the sleeve S and end flap 5, and side flap 9 is folded over on line L2 on side flap 7 to complete the formation of the closure. Sleeve S is a tuck-in sleeve, i.e., a sleeve which extends out of the bag at the valve corner of the bag, an outer part of the sleeve being folded under and tucked in between the remainder of the sleeve and valve flap 3 after the bag has been filled. In accordance with this invention, sleeve S is also a so-called cuffed sleeve, having a cuff C by means of which it is secured by pasting to the inner end of the valve flap 3 in such manner as to provide ample space underneath the sleeve for tucking in the folded outer portion of the sleeve.

As shown in FIGS. 1 and 2, sleeves S are formed from a continuous web W of suitable valve sleeve material, which, for example, may be creped kraft paper. At 11 in FIG. 1 is indicated a draw roll for drawing the web from a supply roll R. Idler rolls such as indicated at 13 are provided for guiding the web around the draw roll. The web has a width somewhat greater than twice the width of the sleeves to be formed therefrom. From the second idler roll 13, the web passes through a cuff cutter generally indicated at 15 which functions to make cuff cuts such as generally indicated at 17 in the web recurring at valve sleeve length intervals longitudinally of the web. Each cuff cut defines a cuff C. The cuff cutter essentially comprises a rotary knife 19 and a fixed knife 21 formed to make cufl? cuts of the desired shape, as next described.

As shown in FIGS. 2 and 5 each cuif cut 17 is generally of broad U-shape, including a curved base cut 23 extending transversely-of the web, relatively short side cuts each designated 25 extending generally longitudinally of the web, and outwardly curved wing cuts 27 at the ends of side cuts 25. The latter trail the base portion 23 as regards the direction of travel of the web, which is indicated by an arrow in FIGS. 1 and 2, and wing cuts 27 are at the trailing ends of the side cuts. The side cuts 25 are spaced transversely of the web a distance somewhat greater than the width of the sleeves S to be formed from the web, and are equally spaced on opposite sides of a line corresponding to the longitudinal center line of the sleeves.

From the cuff cutter 15 the web W (now having cuff cuts 17 therein) passes through a creaser comprising upper and lower rotary creasing members 29 and 31 (see FIG. 1) which function to form a crease 33 (see FIG. 2) extending transversely across the web between the ends of the wing cuts 27 of each cuif out. As shown in FIGS. 1 and 2, web W travels horizontally through the creasing members, and thence passes around a horizontal idler roll 35 and vertically downward. In passing downward around idler roll 35, it passes between idler web. As a result of folding back the cuffs, openings are left in the web.

The web W, with the folded-back cuffs C, then travels around an idler roll 39from which it passes to an adjustable cuff register roll 41 and thence to apaster generally indicated at 43. This paster comprises a paste wheel 45 rotating in a paste reservoir 47 and adapted to apply a stripe of paste '49 (see FIG. 2) to one margin of web W. At 51in FIG. 1 is generally indicated an endless belt conveyor trained around pulleys 53 and 55 to have an upper reach inclined downward in forward direction. Pulley 53 is located adjacent the paste wheel 45. The web travels upward between the paste wheel and pulley 53. The latter is positively driven to drive the belt conveyor in the direction indicated'by the arrow on the conveyor in FIG. 1. The web passes around the portion of the conveyor trained around pulley 53 and under a rotary creaser 57. Pulley 53 is formed as a female creaser and rotary creaser 57 acts in conjunction therewith to form two longitudinally extendingcreases 59 (see FIGS. 2 and'6) in the web and in each cuff C located slightly inward'from side cuts 25 of the cuff cuts 17. These creases 59 define the width of sleeves S. The upper reach of the conveyor passes over a table 61. As the web travels along with the upper reach of the conveyor over the table, the side portions '63 and 65 of the web lying outward of creases 59 are folded over at these creases by folding means such as indicated at 67 in FIG. 1 to bring the margins of the web into overlapping relation and to cause them to become pasted together by the stripe of paste 49. The web is thereby converted into a series or string of integrally connected valve sleeves S. In the string, each sleeve '8 comprises a flat tube, one wall of which is constituted by side portions '63 and 65 and the other wall of which is designated 69. Creases 59, on which portions 63 and 65 are folded over, define the side edges of the sleeveor tube S. The sleeve or tube S has a longitudinal tube seam 71 where the margins of the web are overlapped and adhered together by paste 49. At one end (the leading end) of each sleeve or tube S is the cuff C, which is folded back upon the sleeve or tube S. Cuts 25 are located in wall 63, 65 of the sleeve or tube S, on opposite sides of the longitudinal seam 71, and the cuff C extends from one cut 25 around one side edge 59 of the sleeve or tube S, across wall 69 of the tube, and around the other side edge 59 of the sleeve or tube S to the other out 25. The narrow end portions of the cufiwhich lie on the outside of wall 63, 65 are designated C1. Wall 63, '65 of each sleeve or tube S has an extension 73 projecting beyond the cuffed end of the sleeve or tube S, each extension 73 beingintegrally connected along a line such as indicated in phantom at 75 in FIGS. 24 to the next sleeeve or tube S in the string.

The string of valve sleeves S travels off the leading end of the upper reach of conveyor 51, passes under an idler roll 77 and between a pair of draw rolls 79. Thence it passes through a cutter generally indicated at 81 which functions almost completely but not fully to sever the string on lines 75. For example, cutter 81 functions to cut the string at 75a, 75b and 75c as indicated in FIGS. 3 and 4, leaving narrow tongues of the web material such as indicated at 75d interconnecting the individual sleeves S in ,the string. Cutter 81 essentially comprises a rotary .knife83 and a fixed knife 85 formed to make incomplete cuts asdescribed.

The string passes from the cutter 81 between so-called forwarding rolls 87 and thence between so-called snapoff rolls 89. Boththe forwarding rolls and the snap-off rolls are positively driven, but the snap-off rolls 89 are driven at a faster speed than the forwarding rolls 87 so as to cause each successive sleeve S exiting from the nip of the forwarding rolls to be snapped off at the line '75, the narrow tongues 75d tearing apart as appears in FIGS. 2-4. Thus, the sleeves S are segmented from the string.

At 91 is indicated an endless chain trained around sprockets 93, 95, 97 and 99. This chain is driven in the direction indicated by the arrow in FIG. 1. It carries a series of sleeve gripper units each generally indicated at 101. Three such gripper units are shown in FIG. 1. These are spaced at equal intervals along the length of the chain. Each gripper unit comprises a jaw 103 carried by the chain and fixed against movement relative to the chain, and a jaw 105 pivoted at 107 on the chain for pivotal movement relative to the chain between open and closed position realtive .to the jaw .103. The sprockets are so located that the chain has a lower forwardly travelling reach generally aligned with the path of the string of-sleeves -S. Aseach gripper unit 101 comes around with the chain around the sprocket 93 .at the trailing end of the lower reach of the chain, the pivoted jaw of the unit is open as appears in FIG. 1 and the leading end of a sleeve S segmented from the string as previously described enters the gripper unit, the sleeve being forwarded for entry of its leadingend into the gripper unit by a lower forwarding section .109 and an upper forwarding roll 111. The latter is coaxial with sprocket 93. The leading end of the sleeve comes under the fixed jaw 103. Then the pivoted jaw 105 swings closed to grip the sleeve. The action of the pivoted jaw may be under control of any suitable means, such as afixed cam track cooperating with a cam follower on the pivoted jaw.

A sleeve S gripped by a gripper unit '101 on chain 91 is carried along with the lower reach of the chain and delivered into position on end flap 3 of the partially formed closure on one of the series of bags B being fed forward through the bottomer 1. When the sleeve has been carried into proper position on the end flap 3, the pivoted jaw 105 of the gripper unitopens to release the sleeve, and the gripper unit travels up and away with the chain around sprocket 95. An-endless belt 113 trained around pulleys 115 and 117 (the former being coaxial with sprocket 99) holds the sleeve in position on the end flap 3 after the pivoted jaw 105 has opened.

The sleeve forming and delivering means above described is driven in synchronism with the bottomer 1 for delivering a sleeve S for each bag tube B fed through the bottomer, with the delivery of the sleeves phased with the feed of bag tubes so that each sleeve is delivered onto valve flap 3 of a bag tube with the-cuff C of the sleeve overlying the inner end margin of the valve flap 3, i.e., with the crease 33 substantially in register with the inner end edge 119 of the valve flap 3. It will be observed that each sleeve is delivered with its wall 69 and cuff C on the bottom for this purpose. Also, the path of the web W and the string of sleeves S into which the web is formed, and of the individual sleeves segmented from the string, is registered with the path of the bag tubes being fed through the bottomer-so that the longitudinal center line of each sleeve delivered to a bag tube is substantially in register with the center line of the valve flap 3.

Draw roll 11, rotary knife 19, rotary creaser members 29 and 31, cuff-folding roll 37, rotary knife 83 and forwarding rolls 87 are all driven, in synchronism with bot tomer 1, at such speed as to produce one sleeve for each bag tube fed through the bottomer. The drive for these elements may be via a change gear from the bottomer, permitting change of speeds by changing gears for producing sleeves of different length. Paste wheel 45, pulley and female creaser 53, draw rolls 79 and draw roll 11 are driven off the output of the change gear via a variable speed drive which enables adjustment of tension on the sleeve material. Snap-off rolls 89, forwarding section 109 and forwarding roll 111, chain 91 and belt 113 are driven at a speed such as to deliver the sleeves at the same speed as the speed of bag tube feed through bottomer 1. Cuff register roll 41 is adjustable for varying the length of sleeve material between cuff cutter 15 and sleeve cutter 81 to provide for proper registration of cuff cut and sleeve cut. Draw rolls 79, cutter 81 and forwarding rolls 87 are part of a unit 121 which may be adjusted in position so that the distance between forwarding rolls 87 and snap-off rolls 89 may be varied for various sleeve lengths.

From the above, it will be apparent that each completed bag has a closure at one end comprising the inwardly directed end flaps 3 and 5 and the first and second side flaps 7 and 9, with end flap 3 constituting a valve flap. Sleeve S, which is a tuck-in sleeve, and which comprises a flat tube, overlies the valve flap 3. The first side flap 7 is folded over on the outer wall 63, 65 of the sleeve on tube S and the end flap 5, and the second side flap 9 is folded over on the first side flap 7 and adhered thereto by paste P. The sleeve or tube S has the pair of cuts 25 extending inward from one end thereof defining the cuff C, this cuff being folded back on the outside of the sleeve or tube S. The sleeve or tube S is positioned on valve flap 3 with cuff C overlying the margin of flap 3 at the inner end of flap 3 (see FIG. 8) with the sleeve or tube S extending outward over the flap 3. Cuff C is adhered to the flap 3 by the paste at P1.

More particularly, the cuts 25 are located in the outer wall 63, 65 of the sleeve or tube S, and the cuff C extends from one cut 25 around one side edge 59 of the sleeve or tube S, across the inner wall 69 of the sleeve or tube S, and around the other side edge 59 to the other out 25. The sleeve or tube S actually consists of a rectangular section of the valve sleeve material W folded to form the sleeve or tube S with overlapping adhered-together margins in the outer wall 63, 65 forming the longitudinal seam 71, cuts 25 being located on opposite sides of this seam (see FIGS. 2 and 3). The folding back of the cuff leaves extension 73 of wall 63, 65 projecting inward beyond crease 33 which is located at the inner edge of flap 3.

The bag is adapted to be filled by entering a filling spout in the sleeve S and blowing the material with which the bag is to be filled (such as a pulverized or granulated material) into the bag through the spout. After the bag has been filled, it is taken off the spout, and the outer half of the sleeve S is folded under and tucked in underneath the inner half of the sleeve. With the cuff 0, full tuck-in to the point where the original outer end of the sleeve is entered between the cuff C and the overlying portion of the inner wall (the wall 69) of the sleeve is readily accomplished. That is, the cuff C provides space for tucking the sleeve in as far as the inner end edge of flap 3 conceivably to the point where the end of the sleeve would engage crease 33. In this respect, it will be observed that the paste P1 is applied in a relatively narrow band (see FIG. 7) no wider than cuff C, and does not extend outward beyond the edge of the cuff so as to avoid having the bottom wall of the sleeve as viewed in FIG. 8 stuck to flap 3. If it were stuck to flap 3, full tuck-in of the sleeve would be blocked.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above methods without departing from the scope of the invention, it is intended that all matter contained in the above descrip tion or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

l. The method of forming cuffed valve sleeves for application to bags fed through a bottomer, comprising feeding a continuous web of valve sleeve material in a predetermined path, forming cuff-defining cuts in the web at sleeve length intervals in the web, each cuff-defining cut including a base cut extending transversely of the web and side cuts extending in trailing direction from the ends of the base cut, folding back the cuffs defined by the cuts, folding over side portions of the web on lines located inward of the side cuts to bring the side margins of the web into overlapping relation and adhering said side margins together thereby to form a continuous string of integrally connected flat tubular valve sleeves each having a foldedback cuff at one end, and segmenting each individual valve sleeve from the string for application to a bag by forming a line of weakness across the string at the trailing end of the leading sleeve of the string and snapping off the leading sleeve at said line of weakness by accelerating it relative to the speed of Web feed.

2. The method of claim 1 wherein the cuffs are folded back by feeding the web over a guide and changing the direction of web travel at the guide to cause the cuffs to project out from the web and then causing the cuffs to engage a member which folds them back on the web.

3. The method of claim 2 further including the step of forming creases in the web extending transversely of the web between the ends of the side cuts to facilitate folding back the cuffs.

4. The method of claim 3 further including the step of creasing the web on the lines located inward of the side cuts after the cuffs have been folded back.

References Cited in the file of this patent UNITED STATES PATENTS 971,780 Parrish Oct. 4, 1910 2,216,212 Potdevin et al. Oct. 1, 1940 2,955,517 Honsel Oct. 11, 1960 

1. THE METHOD OF FORMING CUFFED VALVE SLEEVES FOR APPLICATION TO BAGS FED THROUGH A BOTTOMER, COMPRISING FEEDING A CONTINUOUS WEB OF VALVE SLEEVE MATERIAL IN A PREDETERMINED PATH, FORMING CUFF-DEFINING CUTS IN THE WEB AT SLEEVE LENGTH INTERVALS IN THE WEB, EACH CUFF-DEFINING CUT INCLUDING A BASE CUT EXTENDING TRANSVERSELY OF THE WEB AND SIDE CUTS EXTENDING IN TRAILING DIRECTION FROM THE ENDS OF THE BASE CUT, FOLDING BACK THE CUFFS DEFINED BY THE CUTS, FOLDING OVER SIDE PORTIONS OF THE WEB ON LINES LOCATED INWARD OF THE SIDE CUTS TO BRING THE SIDE MARGINS OF THE WEB INTO OVERLAPPING RELATION AND ADHERING SAID SIDE MARGINS TOGETHER THEREBY TO FORM A CONTINUOUS STRING OF INTEGRALLY CONNECTED FLAT TUBULAR VALVE SLEEVES EACH HAVING A FOLDEDBACK CUFF AT ONE END, AND SEGMENTING EACH INDIVIDUAL VALVE SLEEVE FROM THE STRING FOR APPLICATION TO A BAG BY FORMING A LINE OF WEAKNESS ACROSS THE STRING AT THE TRAILING END OF THE LEADING SLEEVE OF THE STRING AND SNAPPING OFF THE LEADING SLEEVE AT SAID LINE OF WEAKNESS BY ACCELERATING IT RELATIVE TO THE SPEED OF WEB FEED. 